Mixing valve



2 sHEETs--SHEET 2 vA Y Sept. 2, 1952 Filed Nov. 28. 1947 l v INVENTR.

' NORMAN L. HElm-:s WM ,JM

/2 fg- 5 L /'s ATTORNEY Patented Sept. 2, 1952 MIXING VALVE Norman L. Heikes, San-Pablo, Calif., assignor to W. Kenneth Rosenberry, Oakland, Calif., doing business as Berkeley Scientific Company, Richmond, Calif.

Application November .28, 1947, Serial No. 788,343

My invention relates to mechanism for equalizing the delivery pressure of liquids supplied from separate sources; and also for mixing such liquids and controlling the temperature of the mixture.

It is among the objects of my invention to provide a fitting by which the delivery pressures of liquids supplied separately from dilerent sources under variable pressures are automatically equalized, regardless of variations of pressure at any source.

Another object of my invention is to provide mechanism for automatically regulating the supply of liquids from different sources supplied at varying temperatures for automatically maintaining a predetermined temperature of the mixture at a point of common delivery.

Another object is to provide a mixing device by which water or other liquids supplied from separate sources under variable conditions of pressure and temperature may be automatically regulated to maintain a predetermined temperature of mixed liquid at a point of delivery regardless of variations in pressure and/or temperature at any source.

Another object is to provide a pressure and temperature regulating device for water mixers embodying improved features of construction and operation, and which may be easily installed with standard ttings' in conventional installations.

The inventionvpossesses other objects, some of which with the foregoing will be set forth at length in the following description wherein are explained those forms of the invention which have been selected for illustration in the drawings accompanying and forming a part of this specification. In said drawings, illustrative forms of the invention are shown, but it is to be understood that it is not limited to those forms, since the invention as set forth in the claims may be embodied in a plurality of other forms.

In the drawings; V

Figure 1 is a plan vieW of the control mechanism of my invention, parts being broken away and shown in section.

Figure 2 is an end elevation of the device of Figure l, parts being broken away and shown in section.

Figure 3 is a front elevation of the device of Figure 1, parts being broken away and shown in section. v

Figure 4 is a vertical sectional view, the plane of the section being indicated by the line 4-4 of Figure 1.

Figure v5 is a fragmental sectional view, the

3 Claims. (Cl. 236-12) plane of the section being indicated by the line 5-5 of Figure 1.

Figure 6 is a sectional View of the device, the plane of the section being indicated by the line 6 6 of Figure 1.

Figure 7 is a longitudinal mid-sectional view of the pressure equalizing mechanism for. use independently of temperature control.

In terms of broad inclusion, the device of my invention comprises a liquid delivery tube connected to two different sources of liquid supply separately deliverable through the tube at spaced outlets. Pressure responsive means, for example a floating piston movable within the tube to cover and uncover the inlet ports to varying degrees. automatically equalizes the pressures at which the two liquids are maintained within the control tube. Where equalized pressures only are required, the spaced outlets may be positioned at any convenient locations and may be independently connected to desired delivery points for mixed or unmixed delivery of the liquids.

Where it is desired to control the temperature as well as the pressure of the outgoing liquids the outlets of the control tube are connected to a mixing chamber and are spaced in a manner such that they may be covered and uncovered to varying degrees by a valve movable by temperature responsive means, such as a thermostat, for automatically maintaining a predetermined temperature of the mixed liquids within the chamber. Manually operable means are provided'for adjusting the thermostat to respond to temperature changes above and below a selected degree, whereby the mixed liquids may be maintained at a desired delivery temperature.

In terms of greater detail, and in its preferred embodiment, the device of my invention comprises a housing I forming-a mixing chamber provided with spaced inlets 2 and 3 havingconnections 4 and 6 respectively to separate sources of supply of water or other liquid; and also provided with a delivery outlet 1 to which a delivery connection 8 is connected. The housing is preferably a metal casting having one open face over which may be secured a cover 9 seating upon a gasket I I and secured to the housing by suitable securing means such as screws l2. The lconnections 4, 6 and 8 may be ordinary pipe threaded into the inlets and outlets. A baiiie I0 is positioned within the mixing chamber over the outlet 'l to insure eiective mixing of liquids before leaving the chamber.

The pressure equalizing portion of my device comprises a control tube or cylinder I4 having spaced inlet ports I6 and I'I opening into annular channels I 8 and I8a cut interiorly of the tube I4 and forming inlet passages. A piston I9 is closely litted for sliding movement within the cylinder I4. The piston I9 has hollow ends and is provided with a substantially central partition 2I positioned between the inlet ports I6 and I1, The hollow end portions of the piston extend axially in opposite directions from the partition and are provided with ports 22 and 23 positioned to register with the ports I6 and I1, and/or the channels I8, I8a into which said ports open, to varying degrees ranging from substantially full opening of the ports at one or the other side of the piston partition 2I and substantially complete closure of the -ports upon the opposite ,side of the piston partition.

The piston I9 is mounted for `'free axial movement within the cylinder I4; and the ports 22 and 23 are arranged to overlap the ports Ii and I1 and connecting channels I8 and I8ar to varying degrees. The effective pressure Within the cylinder from each source of fluid supply is controlleol by the degree of! registry ofl the ports 22 and 23 with tho ,channels I8 and I8@ andv ports I9 and l1. Pressure from the source supplying liquid upon one side of the piston is opposed by the pressure of the source supplying liquid to the cylinder through the 'inlet ports upon the opposite sido of the piston partition. Any change Ain pressure u pon either sidev of the piston results in a movement, impelled by the excess pressure upon the high pressure side, such as to decrease the opening of the inlet port on the high pressure side and increase the opening of the inlet port upon the low pressure side until equilibrium is restored.

In the preferred embodiment illustrated in the drawings, the pressure equalizing means is mounted within the mixing( chamber by means of clamps 25 securing the tube I4 in a normal seated position with the ports I9 and I1 communicating with the inlets 2 and 3 through ports 21 and 2,8. Gaskets 29 provide seats `for the tube I4 sealing the connection between the ports I5 and I 1 and the corresponding inlet ports 21 and 28. The ends of the tube I4 areY closed by plugs 3|. Cylindrical screens 33 are preferably mounted in the inlets 2 and 3 over the ports 21 and 28.

The Piston i9 is provided with ports 33 and 34 movable to register in varying degrees with delivery ports 36 and 31 in the wall of the tube I4. Preferably a plurality of the ports 33 and 34 are 4 provided in circumferentially spaced relation to register with` internal circumferential channel grooves 38 and 39 communicating with the delivery ports 36 and 31. The axial position of the ports 33 and 34 relative to the grooves 38 and 39 is such as to permit liquid to floW from each side of the piston through the corresponding delivery ports and 31 into the mixing chamber regardless of the position of the piston between its normal .limits- Checl; valves 4I are mounted within the piston I9 upon opposite sides of the partition 2! between the ports 22 and the ports 33 at one side and the ports 23 and 34 at the other side. The valves 4I are spring loaded by means of springs 4,2 seated against collars 43 threaded or otherwise secured Within the piston. The check valves are displaced against the pressure of the springs 4 2 by normal delivery pressure of liquid supplied to the piston through the inlet ports 22 and 23,

so that liquid may be delivered through the ports of pressures upon opposite sides of the piston such as might otherwise result from the mixing of the liquids in the mixing chamber.

Thermostatic means are yprovided for regulating the mean temperature of the mixed liquids supplied through the inlet connections. Said means .comprises a sleeve 48 slidably mounted upon the tube I #l between the ports 33 and 31, and movable as a valve to open and close said ports to oppositely varying degrees ranging from substantially complete closure to substantially complete opening.

The valve sleeve 49 is actuated by a lever 41 pivoted upon a pivot screw 48, mounted upon the baiile I9. The lever is provided with a pin 49 engaging an annular groove 5I in the outer surface of the sleeve. The lever 41 is provided with an arm 52 to which the outer end of a bimetallic stri-p, preferably spirally wound to form a thermostat coil 53, is connected. A lip 54 bent secures the coil to the arm.

The inner end of the thermostat coil 53 is secured to a shaft 51 extending into the mixing chamber. Preferably the shaft 51 is journalled upon the cover plate 9 in a bearing block 58 threaded into a recessed lug 59 upon the cover plate 9. The block 58 and lug 59 also cooperate as a packing gland for the shaft, the inner end of the block serving to press a packing ring 9| against a flange 62 carried by the shaft within the back of the recessed lug. 'I'he ange 62 prevents axial movement of the shaft, and the packing ring 6I prevents leakage of liquid from the mixing chamber past the shaft. A handle 63 is secured upon the outer end of the shaft 51.

The shaft 51 and thermostat coil 53 are mounted upon the cover plate as an assembly unit. As the cover is placed over the open face of the housing, the lip 5.4 of the coil slides into interlocking engagement with the slotted lever arm 52, thereby facilitating the assembly of the parts.

The thermostat 53is so shaped and connected as to engage and hold the lever 41 and the valve sleeve 48 in operative positions within the normal range of movement thereof. The position of the sleeve 49 along the tube I4, relative to the ports 33 and 31, may be adjusted by means of the handle 63 and shaft 5,1. By turning the handle to a selected point, the sleeve may be moved to obtain a predetermined degree of opening of each of the portsv 36 and 31 and a fixed ratio of the flow of liquid therethrough. Preferably a scale 64 is provided on the face of the cover plate 3, readable in association with thehandle, for indicating'the approximate position of the sleeve. Where the sources of liquid are normally maintained at a, known' and more or less constant temperature, the scale 64 may be calibrated in terms of temperature. yIn such cases, an initial setting of the handle to a selected position will position the sleeve 46 at a point proportioning the flow of liquid from the twov sources to obtain substantially the desired temperature of the outgoing mixed liquids.

In operation, the device is connected in cony ventional manner into a liquid supply system,

such for example as the hot and cold water supply connections to a shower bath or other delivery xture. Inv such a system, the cold water supply is connected to the inlet 2, and the hot water supply to the inlet 3.. The outlet. connection 8 is. connected to the delivery fixture through a suitable delivery control valve, :not illustrat'ed, bywhich the flow can be regulated.

The handle 63 is set in a position'corresponding to a desired delivery temperature, andthegdelivery control valve is opened permit nowl at a desired rate. The pressures at which the" liquids from the two supplies are delivered are automatically equalized by theoper'ation of the piston I9 is deliveredvthrough the outlet connection 8 at corresponding temperature.

In eventthe temperature of the hot water supply is reduced, the mixture will become correspondingly cooler. As the temperature of the mixture is reduced, the thermostat coil 53 will contract and thereby move the lever 41 and valve sleeve 46 to the right, as viewed in Figure 1 of the drawings. This movement will decrease the flow of cold water from the cold inlet 2 and increase the flow of hot water from the hot inlet 3 suciently to cause the mean temperature of the mixture to be restored to the temperature for which the handle was initially set. Should the temperature of the incoming hot water be increased, the resulting increase in the temperature of the mixture causes the coil 53 to expand. In that case, the sleeve 46 is moved to the left to maintain the set temperature by reducing the hot water supply and increasing the cold water supply.

In case the Water within the mixing chamber is cold when the. handle 63 is set for a selected delivery temperature, the thermostat will be placed under tension such as to move the sleeve 46 to substantially fully close the cold water port 33 until such time as the entry of hot Water raises the temperature within the mixing chamber up to the degree required for opening the port 36 sufficiently to obtain the desired tem perature of mixture.

The temperature and pressure controls cooperate to insure delivery of the mixed liquids under constant conditions of temperature and pressure regardless of changes in either temperature or pressure, or both. Slow changes in temperature, such as may result from heating of the supply pipes, or exhausting of the hot Water supply, are automatically compensated for, within the limits of the supply temperatures, by the thermostatically controlled valve lit. Rapid changes, such as may occur when the ow of water is turned on or off at some other outlet in the same system, are instantly compensated for by the pressure equalizing piston.

While the pressure equalizing means of my invention is primarily useful in a mixing device where temperature is also a factor to be controlled, it may be used in systems where control of the delivery pressure only is required. In such a system, liquid from two different sources may be introduced into a control tube H through supply connections 12 and 13 upon opposite sides of a piston 14 movable in response to diierences in pressure upon opposite sides of the piston, as in the case of the tube i4 and piston I9 above described. The delivery connections may be arranged at any point upon opposite ends of the tube, as for example in the manner illustrated in Figure 7.

I claim:

1. A device for mixing and delivering liquids under controlled conditions of temperature and pressure comprising, a housing provided with spaced inlets for supplying liquids from dilTerent sources of supply and an outlet for the mixed liquids, a cylinder mounted within the housing, said 4cylinder being provided with spaced inlets communicating with the housing inlets and spaced outlets opening into the housing, a piston within the cylinder movable in response to variations in pressures of the liquid supply to cover and uncover the inlets to varying degrees for equalizing the pressures of the liquids within the cylinder, a sleeve mounted upon the cylinder and movable thereon to open and close the outlets to varying degrees, and temperature responsive means for actuating the sleeve to maintain a predetermined mean temperature of the mixed liquids within the mixing chamber.

2. In a valve for equalizing the pressures of separate streams of hot and cold water and delivering the equalized streams separately into a mixing chamber, a housing constituting the mixing chamber, a cylinder closed at its opposite ends and fixed in the housing, separate passages for the hot and cold streams in the housing and cylinder and opening respectively in opposite ends of the cylinder, a hollow piston open at each end and having a central transverse partition and slidably disposed in the cylinder, inlet ports in said piston Wall on each side of the partition and spaced whereby in central position of the piston, each inlet port is half open into an annular recess and half closed by the cylinder Wall, a delivery passage through the piston and cylinder on each side of the partition and opening into the mixing chamber in a delivery port, a sleeve valve slidably disposed about the cylinder and arranged whereby in central position each delivery port is half closed and half open, and temperature responsive means disposed in the mixing chamber for actuating the sleeve valve to proportion the flow from each delivery port.

3. In a valve for equalizing the pressures of separate streams of hot and cold water and delivering the equalized streams separately into a mixing chamber, a housing constituting the mixing chamber, a cylinder closed at its opposite ends and xed in the housing, separate passages for the hot and cold streams in the housing and cylinder and opening respectively in opposite ends of the cylinder, a hollow piston open at each end and having a central transverse partition and slidably disposed in the cylinder, inlet ports in said piston Wall on each side of the partition and spaced whereby in central position of the piston, each inlet port is half open into an annular recess and half closed by the cylinder wall, a delivery passage through the piston and cylinder on each side of the partition and opening into the mixing chamber in a delivery port,

l a check valve allowing flow only toward the delivery passage and arranged on each side of the partition between the inlet port and the delivery passage, a sleeve valve slidably disposed about the cylinder and arranged whereby in central position each delivery port is half closed and half open, and temperature responsive means disposed in the mixing chamber for actuating the sleeve valve to proportion the flow from each delivery port.

NORMAN L. HEIKES.

(References on following page) 7 REFERENCES CITED The following references are of record in the file of this patent:

y UNITED STATES PATENTS Number Name Date 990,557 Holman Apr. 25, 1911 1,807,040 Leonard May 26, 1931 1,948,044 Myers Feb. 20, 1934 Number 8 Name Date Gibbs Jan. 24, 1939 Young Sept. 12, 1939 Leonard Oct. 10, 1939 Mahon May 14, 1940 Ruegg et al lJuly 29, 1941 Trautmann et al. Jan. 7, 1947 Stephens July 1, 1947 

